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How To Dice An Onion

Onion is one of the most common ingredients in any recipe. Do you know how to dice an onion? Learn how, and pick up any supplies you need from my affiliate links that earn me a commission if you buy.

Pile of diced onion

Growing up, I’m sure my mom cut onions at some point, but she never taught me. I find that so many people never learned from their parents, aunties, and grandmas like we used to in previous generations.

I learned to dice onions, but I have no idea from where or who taught me. I’ve taught countless friends – plus my husband and kids.

If my husband and kids can figure this out, anyone can. They may not do it as fast as I do (my record is about 34 seconds), but they dice onions in about a minute.

You. Can. Too.

How to dice an onion

Read on to see step by steps on exactly how to dice an onion, or check out the video if you prefer. The photo show each step to ensure you don’t get confused!

The onion I used in this video? I used half of it to make the Instant Pot chicken paprikash I shared yesterday. The rest went into the pulled pork I’m making for dinner tonight.

What will you make? I shared a few of my favorite recipes that use onion at the bottom of this article. Check them out!

Tips on How to Dice an Onion

First of all, make sure to use a good cutting board. You don’t want to accidentally ruin your counter or dull your knife by cutting on a plate or other surface.

Ensure your knife is sharp. Hint: The one I used in my video needs to be sharpened. The sharper the knife, the easier it cuts which reduces the force you need to use to cut. That actually reduces knife injuries because you can control where the knife goes better.

Related? Use a large enough knife. My husband used to use a paring knife to cut onions, but the wrong size knife can be dangerous, too. Use a vegetable knife or a chef’s knife.

That also means that you shouldn’t use a serrated bread knife – they’re great for tomatoes and lettuce, however. And don’t use a filleting knife either. I want you safe!

You can also dice onion before you need it. Go ahead and cut up a whole onion even if you need only half a cup. You can refrigerate it for a few days in a tightly sealed container to use in another recipe. Don’t freeze it though, as the water in onion bursts the cells and makes it mushy.

And when you cut your onion, remember that until you make the final cut to dice your onion, you need it to stay together. Don’t cut off the hairy root end or slice all the way through until the end.

Steps on How to Dice an Onion

To start, slice off the top of the onion. This is not  the hairy root end.

Set the onion cut side down with the hairy end sticking up. Slice it in half through the root end so you have two halves that look like this.

Onion sliced in half

Peel off the dry skin from each half. Discard the peel.

Remove onion skin

Set one onion half on your cutting board with the missing top side facing your knife hand. Use your nondominant hand to hold the onion half in place.

Make three “smiley face” cuts horizontally. Make sure not to cut through the root end. No matter what size onion you dice, three cuts work.

Cut onion smiley faces

Once you make those three cuts, your onion should look like this from the side.

Three onion smiles

Next, slice vertically three times, again ensuring you don’t cut through the root.

Slice across onion

Finally, slice down to make the final cuts as shown.

Slice onion into dices

The closer you make this final cut, the finer your dice. The further apart you make each cut, the larger the dice.

It’s truly this easy. Repeat with your other onion half, and start cooking!

Did you know it’s this easy learn how to dice an onion?

My favorite recipes that used diced onion

How to dice an onion in under one minute with this easy video tutorial and step by step photo instructions. Learn how to cook and easily cut onions for any recipe. #onions #howto #cooking101 #tutorial
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